Magnetic recording medium comprising a surface treatment layer provided on the magnetic layer of specified fluorocarboxylic acid amine salts

Abstract

Disclosed herein are a magnetic recording medium comprising a surface treatment layer provided on the surface of a magnetic coating film by use of a novel surface treatment agent capable of bonding to both magnetic particles and a binder in the magnetic coating film, and a process for producing the magnetic recording medium. It is possible to realize, with good productivity, a magnetic recording medium having excellent wear resistance and high reliability.

What is claimed is: 
     
       1. A magnetic recording medium which comprises a coating magnetic film comprising magnetic particles in a binder, the magnetic film provided either directly on a substrate or on an under layer provided therebetween, wherein the surface of the magnetic film is treated with a fluorocaboxylic acid salt of amine, comprising at least one selected from the group consisting of fluorocarboxylic acid salts of amine represented by the following general formula (I) or (II):   R.sub.f --CO.sub.2.sup.-+ N(R.sub.1)(R.sub.2)--A--X        (I)       X--A--N(R.sub.1)(R.sub.2).sup.+- O.sub.2 C--R.sub.f '--CO.sub.2.sup.-+ N(R.sub.1)(R.sub.2)--A--X                                 (II)     wherein R 1  and R 2  each represent a hydrogen atom or an alkyl group having one to four carbon atoms, A represents a divalent organic group selected from alkylene and arylene groups, X represents a functional group capable of bonding to a binder, selected from azido, vinyl, iodo and bromo groups, and R f  and R f  ' each represent a fluorocarbon group selected from perfluoropolyether and perfluoroalkyl groups.   
     
     
       2. The magnetic recording medium as set forth in claim 1, wherein the fluorocarboxylic acid salt of the amine has a perfluoropolyether chain as a fundamental skeleton thereof. 
     
     
       3. The magnetic recording medium as set forth in claim 1, further comprising a lubricating layer on the surface treatment layer, the lubricating layer comprising a fluorochemical lubricant. 
     
     
       4. The magnetic recording medium as set forth in claim 3, wherein the fluorochemical lubricant has a perfluoropolyether chain as a fundamental skeleton thereof. 
     
     
       5. In a magnetic recording medium comprising a substrate, a magnetic coating film which is provided either directly on said substrate or on an under layer provided therebetween and which contains magnetic particles in a binder, and a surface treatment layer formed on said magnetic film, the improvement wherein said magnetic particles bond to a fluorocarboxylic acid in said surface treatment layer and said binder bonds to fluorocarboxylic acid salt of an amine comprising at least one selected from the group consisting of fluorocaroxylic acid salts of amine represented by the following general formula (I) or (II):   R.sub.f --CO.sub.2.sup.-+ N(R.sub.1)(R.sub.2)--A--X        (I)       X--a--N(R.sub.1)(R.sub.2).sup.+- O.sub.2 C--R.sub. '--CO.sub.2.sup.-+ N(R.sub.1)(R.sub.2)--A--X                                 (II)     wherein R 1  and R 2  each represent a hydrogen atom or an alkyl group having one to four carbon atoms, A represents a divalent organic group selected from aklylene and arylene groups, X represents a functional group capable of bonding to a binder, selected from azido, vinyl, iodo and bromo groups, and R f  and R f  ' each represent a fluorocarbon group selected from perfluoropolyether and perfluoroalkyl groups.   
     
     
       6. The magnetic recording medium as set forth in claim 5, wherein the fluorocarboxylic acid salt of an amine has a perfluoropolyether chain as a fundamental skeleton thereof.